The use of analog-to-digital converter technology is well known and widely used to convert information such as voice and data from an analog domain to a digital one. As is well known in the art, signal information can more easily be processed, transmitted and manipulated much more effectively once analog signals have been converted into the digital domain.
Past ADC designs were constructed such that the ADC continually attempted to handle worst case signal conditions no matter what type of signal was received. Even when receiving a strong signal with low signal-to-noise requirements, the ADC continually worked the incoming signal as if it were a degraded signal. Those skilled in the art will further recognize that an ADC's input signal dynamic range is purposely made large order to handle a broad spectrum of signal and noise inputs. Thus the ADC is over designed for certain signal conditions and protocol requirements. This “over design” result in both a greater degree of circuit design area and an excessive current drain on a portable device.
In many instances, the device is not receiving signals under worst case signaling conditions but,nonetheless, is required to operate in this manner in this low efficiency mode due to required specifications. Thus, in order to obtain the lowest noise figure and best matching in the ADC, the ADC is designed for worst case signaling conditions. Ultimately, this approach becomes costly since the ADC cannot be dynamically changed based on input signal conditions.
Thus, the need exists to provide an adaptive ADC that can dynamically control its dynamic range enabling current drain and mathematical requirements to be varied in order to best accommodate the instantaneous RF signaling environment. This would enable the ADC to conserve power under optimal signal conditions yet alter dynamic range when those conditions cross some predetermined threshold.